Drum filter



J. E. KRYNSKI Oct. 17, 1967 DRUM FILTER Filed Sept. 9, 1965 I G 2 INVENTOR ubmv E. Kkr/vsx/ E51,. m

ATTORNEYS United States Patent 3,347,389 DRUM FILTER John E. Krynski, East Moline, 11]., assignor to Ametek, Inc., New York, N.Y., a corporation of Delaware Filed Sept. 9, 1965, Ser. No. 486,163

. 2 Claims. (Cl. 210-401) ABSTRACT OF THE DISCLOSURE A drum filter employing cloth belt filtering media in which the belt medium is maintained in alignment while shrinkage, stretching thereof and wrinkling of same during use are reduced to a minimum without employing auxiliary tracking equipment.

This invention relates to drum filters which employ cloth belt filtering media, and particularly to an improved drum filter of this type in which belt alignment is maintained while shrinkage, stretching and wrinkling of the cloth belt are minimized.

The principal object of the invention is to provide a drum filter in which the belt medium is maintained in alignment while shrinkage, stretching and wrinkling are reduced to a minimum without employing auxiliary tracking equipment.

Another object of the invention is to provide such a filter in which the belt medium is held onto the drum by a drawstring arrangement in combination with resilient means surrounding both edges of the drum to provide a seal preventing the escape of solids in the filtrate from the side edges of the drum.

In one aspect of the invention, a drum type filter may comprise a drum having trunnions that are journaled for rotation in aligned bearings at the top of standards for supporting the drum. The drum may comprise peripheral pockets, each connected by radial ducts that lead along the axis of the drum to a valve means that provides a subatmospheric pressure to the tubes.

In another aspect of the invention, the periphery of the drum may be provided with pockets that are formed by axially extending, peripherally spaced bars that extend between peripherally extending ring elements at each end of the drum. There may be provided a perforated sheet surrounding the exterior of the drum and resting on the ring means to which it is attached.

In another aspect of the invention, the ring means may take a form having dovetail cross section that is open. A resilient insert may be located within the outermost dovetail ring element, and it may fill the open dovetail and extend radially a distance beyond the ring. The ring may include an axially extending flange forming a pocket with the side of the ring at the outermost edge of the drum.

In still another aspect of the invention, the resilient insert may extend about the flange and include a hollow, annular portion within the pocket formed by the flange and ring side.

In a further aspect of the invention, a cloth filtering medium, wider than the drum, may be employed in belt fashion to surround a substantial portion of the drum and to pass over idle and discharge rolls. The belt may include a seam along its edge, through which a resilient cable extends that is drawn tight enough to cause the belt to wrap around the edges of the drum and to compress the hollow, annular portion of the resilient insert at each end of the drum.

The above, other objects and novel features of the improved filter will become apparent from the following specification and accompanying drawing which are merely exemplary.

3,347,389 Patented Oct. 17, 1967 In the drawing:

FIG. 1 is an end elevational view, parts being broken away, of a drum filter to which the principles of the invention have been applied; and

FIG. 2 is a view looking in the direction of the arrows along line 22 of FIG. 1.

Referring to the drawing, the principles of the invention are shown as applied to a drum filter including a hollow drum 10 having end walls 11 from which trunnions 12 extend that are journaled in aligned bearings 13 atop standards 14. The drum 11 may comprise an impervious peripheral shell 15 having axially extending, peripherally spaced elements 16 forming pockets 17 therebetween. The outer edges of elements 16 may support a perforated shell 18.

At each end of the drum 10 there may be provided ring means 19 which in the embodiment disclosed is shown as two rings 20, 21, each having an open dovetail cross sectional construction. The pockets 17 are formed by the axial elements 16 abutting the rings 20, and the perforated shell 18 extends over ring 20 but short of ring 21. Rings 20, 21 may include flanges 22, 23 that extend parallel to shell 15. A resilient, annular member 24 preferably made of a soft rubber may include a portion 25 that fills the hollow dovetail of ring 21 and which extends radially therebeyond. Member 24 may include a portion 26 that wraps around the flange 23 of ring 21 and is connected to a hollow annular portion 27 that lies between the flange 23, the surface 15 and the outer wall of ring 21. The annular space 28 within portion 27 provides a degree of resilience for a purpose to be described.

A cloth belt 29 that is substantially wider than drum 10 is wrapped around a substantial portion thereof and passes over a roll 30 as well as a breakup roll 31 that causes the collected solids to be discharged from belt 29 and to fall into a hopper 32 (FIG. 1).

The width of belt 29 is such that it provides an overhanging portion 33 at each end of dmm 10. Its edges include a seam 34 through which a resilient drawstring or cord 35 is threaded. The arrangement is such that the overhanging portions 33 compress the resilient, hollow annular portion 27 of member 24, providing a seal thereby preventing the loss of material past the ends of drum 10. This sealing arrangement provides a wide seal area extending from the edge of perforated plate 18 along the top of the portion 26 and around the portion 27 to at least its midpoint.

Although the various features of the improved drum filter have been shown and described in detail to fully disclose one embodiment of the invention, it will be evident that changes may be made in such details and certain features may be used without others without departing from the principles of the invention.

What is claimed is:

1. In a drum filter, the combination comprising a drum mounted for rotation about a horizontal axis; a discharge roll mounted for rotation about an axis parallel with said drum axis; channel-shaped annular means fixed to said drum inwardly of the edges thereof, said annular means including flange means parallel with and spaced from the periphery of said drum and forming an annular recess about each edge of said drum; a resilient annular member Within said channel-shaped annular means, extending radially therebeyond, said resilient member extending around said flange means, and extending axially beyond the end of said flange means; an endless cloth belt having a width transversely substantially greater than the width of said drum and roll and having its edges overhanging freely from the edges of said drum, said edges of said belt including seam means therealong; and a resilient tensioning means in said seam means of less length than said belt, whereby said overhanging edges of said belt are drawn radially inwardly in contact with the resilient annular member along a substantial surface area parallel with said drum and a substantial area of the por tion within said annular recess.

2, In a drum filter as in claim 1, wherein said resilient member extends around said flange means and includes an annular hollow portion within said annular recess.

References Cited UNITED STATES PATENTS 4- 6,017,997 1/1962 Hawkes et a1. 210-401 3,143,502 8/1964 Krynski 210401 3,144,409 8/1964 Jauhola 210-401 X FOREIGN PATENTS 147,577 11/ 1954 Sweden.

OTHER REFERENCES G. A. Valente, A New Idea in Sludge Dewatering, The Permutit C0., Bulletin E, 49 Midland Ave., Paramus, NJ.

REUBEN FRIEDMAN, Primary Examiner.

J. ADEE, Assistant Examiner. 

1. IN A DRUM FILTER, THE COMBINATION COMPRISING A DRUM MOUNTED FOR ROTATION ABOUT A HORIZONTAL AXIS; A DISCHARGE ROLL MOUNTED FOR ROTATION ABOUT AN AXIS PARALLEL WITH SAID DRUM AXIS; CHANNEL-SHAPED ANNULAR MEANS FIXED TO SAID DRUM INWARDLY OF THE EDGES THEREOF, SAID ANNULAR MEANS INCLUDING FLANGE MEANS PARALLEL WITH AND SPACED FROM THE PERIPHERY OF SAID DRUM AND FORMING AN ANNULAR RECESS ABOUT EACH EDGE OF SAID DRUM; A RESILIENT ANNULAR MEMBER WITHIN SAID CHANNEL-SHAPED ANNULAR MEANS, EXTENDING RADIALLY THEREBEYOND, SAID RESILEINT MEMBER EXTENDING AROUND SAID FLANGE MEANS, AND EXTENDING AXIALLY BEYOND THE END OF SAID FLANGE MEANS; AN ENDLESS CLOTH BELT HAVING A WIDTH TRANSVERSELY SUBSTANTIALLY GREATER THAN 